Separable molded article

ABSTRACT

An article of manufacture including a panel and a tear portion joined at an interface which forms a seal and a weakening line along which the tear is separable from the panel. The weakening line is formed by initially molding the panel or the strip portion to form one of the faces at the interface and using this preformed face as a mold surface to form the complementary sealing face of the other.

United States Patent [72] Inventors EdmundH.Merz

[54 SEPARABLE MOLDED ARTICLE 22 Claims, 19 Drawing Figs.

[52] US. Cl. 220/53, 220142 B, 215/465, 220/24 A [51] lint. B65d 17/24,865d 4 1/0Q [50] Field of mrch 220/53, 54, 24, 42; 25/465 [56]Retell-enemas Cited UNITED STATES PATENTS 3,276,616 10/1966 Lurie 220/533,401,821 9/1968 Bozek 220/54 Primary Examiner-George T. Hall Anomeys-Fred P. Kostka, Joseph E. Kerwin and William A.

Dim-nan ABSTRACT: An article of manufacture including a panel and a tearportion joined at an interface which forms a seal and a weakening linealong which the tear is separable from the panel. The weakening line isformed by initially molding the panel or the strip portion to form oneof the faces at the interface and using this preformed face as a moldsurface to form the complementary sealing face of the other.

PATENIEB AUB24 I97! SHEET 3 0F 5 5 mm :NNE mmI W 7 mm m T L N \mHN. M wA E I a. a: i

mm Q.

5% 0% m WW L m 6 w EDMUND ,H. MERZ HOWARD M, TURNER fig ATT'Y.

PATENTED AUG24|97I GBOL 278 saw u or 5 T JB- l @293 I I 208 .209 2o4INVENTORS ATT'Y.

PATENTED AUG24 |97l SHEET 5 BF 5 INVENTOR EDMUND ll MtRZ BY HOWARD MTMWER K W ATT Y SEPARABLE MOLDED ARTICLE This application is acontinuation-in-part of US. Pat. application Ser. No. 750,230 filed Aug.5, 1968.

The present invention relates to closures and, more particularly, to aneasy opening closure for containers or the like.

It is a principal object of the present invention to provide a closurehaving a panel and separable tear portion joined along an interfacewhich defines a weakening line created by molding one of the componentsabout a prior formed face, so that the components are joined in sealingrelationship at the interface and separable therealong upon theapplication of a separating force to one of the components.

It is a further object taken in conjunction with the foregoing principleobject to a container with an easy opening closure formed with a paneland a tear portion which is separable from the panel to provide accessto the contents of the container.

IN THE DRAWINGS:

FIG. 1 is. a top plan view of a closure embodying the principles of thepresent invention and applied to a container end, which is shown inphantom lines, to more clearly illustrate the structure of the closure;

FIG. 2 is an enlarged fragmentary sectional view showing the closureapplied to the container and illustrating in phantom lines the tearportion in a partially open position;

FIG. 3 is an enlarged fragmentary cross-sectional view more clearlyillustrating the configuration of the interface defining the weakeningline along which the tear portion is separable from the panel;

FIGS. 4-6 are enlarged fragmentary sectional views similar to FIG. 3 butillustrating different configurations of interfaces;

FIG. 7 is a cross-sectional view of the molding apparatus which may beused to manufacture the easy opening closure illustrated in FIGS. 1-3and showing the apparatus in the closed molding position;

FIG. 8 is an end view of the indexing head of the apparatus shown inFIG. 7;

FIG. 9 is an end view of the stationary mold head of the ap paratusillustrated in FIG. 7;

FIG. l0 is a side elevational view of the indexing head partially incross section and shown in the open position thereof;

F IG'. 1 l is a cross-sectional view of the indexing shaft takengenerally along the lines ll11 of FIG. 7; and

FIG. 12 is a longitudinal cross-sectional view through the indexingshaft taken generally along the lines 12l2 of FIG. 11; and

FIG. 13 is a cross-sectional view of a further embodiment of a closureembodying the present invention;

FIG. 14 is a top perspective view of another novel easy opening closureconstructed in accordance with the present invention, and illustrates abottle cap having an end panel' joined to a peripheral skirt along aweakening line, and a pull tab portion for removing the entire end panelfrom the peripheral skirt;

FIG. 15 is a top perspective view of thebottle cap of FIG. 14, andillustrates the manner in which the pull tab portion is manually graspedand lifted to remove the end panel from the peripheral skirt;

FIG. 16 is an enlarged fragmentary sectional view taken generally alongthe line 16-16 of FIG. 14, and more clearly illustrates the manner inwhich the end panel is joined to the peripheral skirt along theweakening line;

FIG. 17 is a top perspective view of another bottle cap constructed inaccordance with the present invention, and illus trates a tear stripwhich is defined by portions of an end panel and a peripheral skirt ofthe cap;

FIG. 18 is an enlarged sectional view taken generally along line 18-18of FIG. 17, and more clearly illustrates a pair of parallel weakeninglines joining the tear strip to remaining portions of the cap;

FIG. 19 is a top perspective view of the cap with portions removed forclarity, and illustrates the manner in which a pull tab of the tearstrip is grasped for removing the tear strip from a remaining portion ofthe cap.

Referring now to FIGS. l-3, the closure embodying the principles of thepresent inventionis shown in the form of an easy opening closure 10attached to a container 11.

.The easy opening closure 10 comprises a panel 12 and a tear portion 13which is separable fIOIII the panel 12 along interface 14 of the panel12 and tear portion 13 to form an opening 25. The tear portion 13 may beformed with post 15 to which there is connected a pull tab 16. The pulltab.l6 is grasped by the fingers for exerting a force to separate thetear portion 13 from the panel 12. To minimize the force required toinitiate the separation of the tear portion 13, the interface l4 aboutthe post 15 may be formed in the nature of a butt joint 14a which mergeswith the remainder of the interface 14 which as shown may beconfigurated as a scarf joint 14b.

The easy opening closure 19 is shown applied to a container 11comprising generally a body 17 which may be made from any suitablematerial such as metal, plastic or the like. Attached to an open end ofthe body 17 is an end closure or cover 19 having a generally pear-shapedpour opening 21 formed therein. Thecover 19 may be made from materialthe same as or different from the material of the container body 17. Asshown, the cover 19 is made from metal and is suitably attached to thebody 17 as by a double seam 22.

The easy opening closure 10 preferably secured to the underside of theend cover 19 so that the interface 14 is located inwardly of the edge ofthe pour opening 21 to reduce the danger of cutting along the metal orraw edge. At the same time the tear portion 13, which may also bepear-shaped, is disposed over the pour opening 21 so that, uponseparation from the panel 12, the contents of the container 11 which maybe a beverage or the like may be easily removed. The easy openingclosure 10 may be made separate from the end closure 19 and subsequentlyadhered or attached thereto as by a suitable adhesive 23 or otherbonding means.

In accordance with the present invention, the interface 14 is formed bypreforming either the inner face or edge 24 defining the opening 25 inthe panel 12 or the outer face or edge 27 of the tear portion 13 toprovide a finished mold face on which the face of the other member issubsequently formed, as more fully to be explained hereinafter. Thepanel 12 and tear portion 13 may be made from a suitable moldablematerial as, for example, a thermoplastic such as polyethylene,polypropylene or the like, a thermosetting plastic such as a filledphenolic molding powder, or rubber.

The panel 12 and tear portion 13 may each be made from plastic materialsselected from the same chemical class having the same or differentphysical properties or may be selected from different classes. Forexample, the panel 12 and tear portion 13 may both be made frompolypropylene selected from the same class, but the polypropylene usedfor the panel 12 may differ from the polypropylene used for the tearportion 13 in respect of physical properties such as the melt flow,density or the like. Also, to illustrate the use of different chemicalclasses of material, either the panel 12 or tear portion 13 may be madefrom polypropylene while the other may be made from polyethylene. Theparticular material used will be determined to some extent by thecontainer structure, container use, and in particular by the sealingcharacteristics desired at the interface 14.

The seal at the interface 14 is formed so that the abutting faces oredges 24 and 27 of the panel 12 and tear portion 13, respectively, forma seal which is capable of being separated therealong upon theapplication of a force thereon so that the interface 14 defines aweakening line.

The seal may be achieved by a tight fit of the tear portion 13 withinthe opening 25 so that the frictional forces at the interface 14 resistseparation. To improve the sealing characteristics at the butt joint14a, one or both of the abutting edges,

24 and 27 may be roughened as by knurling or the like. The seal of theremainder of the interface 14 is in the nature of a scarf joint 14bwhich is disposed so as to resist the tendency of the tear portion 13 toseparate under the pressure forces ex- 'erted thereon by the containercontents, such as carbonated 1 beverages or the like, .until a manuallyseparating force is plied as more fully to be explained hereinafter.

Further embodiments for forming a seal at the interface 14 may be atongue and groove joint 14c as-illustrated-inFlG. 4, an interfacedovetail joint 14d as shown in' FIG. 5 or a sawtooth joint 14e as shownin FIG. 6. The joints 14b, 0 and d are constructed so as to form aninterlock at the interface and thereby permit the reinsertion of thetear portion 13 into the opening. v

The panel 12 and tear portion 13 are preferably each formed by injectionmolding, although it should be readily apparent that other moldingmethods, as for example, compression molding, transfer molding, orimpulse molding may also be used. It should also be mentioned that thepanel 12 and tear portion 13 may each be formed by-the same moldingmethod or may be formed by different molding methods. Although the panel12 having the opening 25 formed therein may be formed or molded firstand used as a mold member to form the tear portion 13. In the preferredform of the invention the tear portion 13 is initially formed and thepanel 12 molded thereabout as more fully to be explained hereinafter.

Referring now to FIG. 7 to 12 there is shown an apparatus 31 forinjection molding of the closure 10. The injection molding apparatus 31comprises generally a stationary head assembly 32 and an indexing headassembly 33. The indexing head assembly 33 is mounted for lengthwisemovement relative to the stationary head assembly 32 from the closedposi- The stationary head assembly 32 includes a molding head 34 havingfastened therein a mold plate 36 for forming the tear portion 13 and amold plate 37 for forming the panel 12 about the tear portion 13. Themold plates 36 and 37 as shown are each formed with a plurality of tearportion cavities 38 and panel cavities 39 for forming the tear portion13 and the panel 12.

Each of the tear portion cavities 38 in the mold plate 36 is formed toshape the outer edge 27 of the tear portion 13 to form the scarf joint14b and the butt joint 14a at the interface 14 of the completed closure10. Projecting from and communicating with each of the cavities 38 is acylindrical or post cavity 40 for forming the attachment post to whichthe pull tab 16 is subsequently attached.

Gates 41 are provided at the upper end of the post cavities 40 forintroducing molten plastic into the cavities 38 and 39. Communicatingwith the gates 41 are runner grooves 42 which are connected to ahorizontal passage 43 which receives p'nstic from a passage 44 injectedtherein through an inlet opening 46 by an injection head 45.

The panel forming cavities 39 are larger than the tear portion cavities38 and include a post opening 46 for accommodating the posts 15 therein,as more fully to be explained hereinafter. Gates 47 enter the cavities38 at the wide end thereof and communicate with runner grooves 48. Therunners 48 communicate with a horizontal passage 49 and a radial passage51 extending to the edge of the head assembly 32 and through which themolten plastic is injected by an injection head (not shown).

The index head assembly 33 includes generally a housing 52 in whichthere is turnably journaled an index head 53. The index head 53 includesa rear annular plate 54 into which there is fixed one end of an indexshaft 56. The index shaft 56 is journaled for rotation in a bearing 55seated in the housing 52. The other end the shaft 56 is supported in asupport assembly 57 for lengthwise sliding and turning movement duringmovement of the index head assembly 33 from the closed position shown inFIG. 7 to an open position shown in FIG. 8. Mounted on the supportassembly 57 is a spring-biased pin 58 which is received in twodiametrically opposed slots 59 or 61 formed in the index shaft 56.Connecting the slots 59 and 61 are helical grooves 62 and 63 into one ofwhich the pin 58 rides during movement from the closed to open moldpositions so that the index head 53 is rotated l within the housing 52.During movement from the open to closed position the pin 58 is preventedfrom entering either the groove 62 or 63 by shoulders 64 and 65 theappropriate one of which depresses the pin 58 so that it does not enterhelical groove 62 or 63 but continues to move along the slot 59 or 61 asappropriate so that the index head 53 does not rotate within thestationary head and move lengthwise therewith.

Restraining the housing 52 against turning as the index head 53 turns isa guide shaft 66 which is fixed at one end to the housing 52 and at itsother slidable within an opening 67 of the support assembly 57.

Fixed to the rear annular plate 54 of the index head 53 is a spacingsleeve 68 to the forward face of which there is fixed a disc 69 todefine a chamber 71 with the annular plate 54. Suitably attached to thedisc 69 is an index faceplate 72 having a pair of tear portion transferplates 73 and 74 inserted therein to cooperate with the mold plates 36and 37 on the stationary head assembly 32 for transferring the tearportions 13 formed in the mold plate 36 to the panel forming mold plate37. The index faceplate 72'is provided with two sets of runner grooves76, horizontal passages 77 and vertical passages 78, which cooperatewith grooves 48, horizontal passage 49 and vertical passage 51 to formconduits through which the plastic flows when the stationary headassembly 32 and index faceplate 72 are in face-to-face relationship asshown in FIG. 7.

The transfer plates 73 and 74 are each formed with sets of retentionfeet opening 79 of generally dovetail configuration. The sets of opening79 are located to be disposed within respective ones of the tearportioncavities 38 of the tear portion mold plate 36. In this manner theplastic flowing into the tear portion cavities 38 also enters theretention feet openings 79 to form retention feet 81 on one side of thetear portion 13. Thus, when the stationary and index head assemblies 32and 33 are separated, the tear portion 13 is retained on the transfermold plates 73 and 74.

For ejecting the retention feet 81 after the panel 12 has been formedthereon, there is provided a pair of ejecting assemblies 82-82 one foreach of the transfer plates 73 and 74. The ejecting assemblies 82-82each comprise a support plate 83 lengthwise slidable within the chamber71 between the disc 69 and rear plate 54. Fixed to the support plate 83are ejecting pins 84 having ejecting fingers 85 extending into opening86 formed in the respective transfer plate 73 and 74, and communicatingwith the retention feet openings 79.

The ejecting assembly 82 is actuated to the ejecting position duringlengthwise movement of the indexing head assembly 33 to open position.To this end, the index assembly stationary housing 52 is provided withan opening 87 and the indexing head rear plate 54 is formed with a pairof diametrically opposed openings 8888, of which one is aligned with thehousing opening 87 when the index head 53 is turned during movement tothe open position. In this position an actuating pin 89 carried by theshaft support assembly 57 extends through the aligned openings 87 and 88and engages the slide plates 83 of one of the ejecting assemblies 82.The other ejecting assembly 82 remains stationary. Upon further movementof the index head assembly 33 toward the support assembly 57 the pin 89is operative to slide the ejecting pins 84 and fingers 85 through theopenings 86 and force the retention feet 81 on the tear portion 13 outof the retention opening 79. In this manner, the plurality of completedclosures 10 are detached from the transfer plate 73 and 74 depending onwhich plate is aligned with the mold plate 36. As shown, the fourclosure units 10 upon ejection remain attached to the sprue and runnerswhich are later detached.

A sprue and runner separating assembly 91 is disposed between each ofthe ejecting assemblies 82-82 and includes a mounting block 92 which isengageably with shoulders 9393 on the ejecting pin support plates 83.Extending from the mounting block 92 is a pair of pins 94 which areslidable through the disc 69 and faceplate 72. As shown in FIG. 8, whenone of the ejecting assemblies 82 is actuated to eject the retentionfeet 81 of a completed group of closures from the index head face plate72, the mounting block 92 is simultaneously moved so that the pins 94project outwardly to break the sprue and runners from the previouslyformed tear portions 13 seated in the upper transfer plate 74.

After the ejection of the closure 10, the indexing head assembly 33 isreturned to the closed position shown in FIG. 7. During the returnmovement the indexing pin 58 rides in one of the linear slots 59 or 61only so that the index head 53 remains stationary within the housing 52.As the index head assembly 33 approaches the stationary head assembly 32the sprue ejecting pins 94 engage the face thereof and are pushedinwardly. At the same time the sprue ejectingpin mounting block 92 inengagement with the shoulder 93 on the slide plate 83 carrying theretention feet ejecting pins 84 is also moved rearwardly so that, whenthe stationary head assembly 32 and indexing head assembly 33 are inface-to-face engagement,

the slide plate 83 is in the fully retracted position shown in 'FIG. 7.

Holding; the stationary head assembly 32 and index head assembly 33 inalignment in the closed position during the molding operation-arelocating pins 96-96 fixed to the stationary head assembly 32 andreceived in complementary located openings 97--97 provided in the indexhead faceplate 72. For controlling the molding temperatures in thestationary head assembly 32 and index headassembly 33 each are providedfluid passages 98 and 99 respectively which are connected to a suitablesource of coolant.(not shown).

Assuming that a set of. previously formed tear portions 13 are retainedin the upper transfer plate 74 and located within respective ones on thepanel mold cavities 39 in the upper half tion to simultaneously form thepanels l2a bout the tear por-.

tions 13 and form tear portions '13 in the tear position-mold cavities38 in the moldnplate 36. This is accomplished by simultaneouslyinjecting molten plastic into-the passage .44 and 51. The molten plasticintroduced into the passage 44 is forced under pressure through thepassage 44, runners 42 and gates 41 into the tear portion mold cavities38. At the same time the molten plastic also flows into the retentionfeet opening 79 in the index head mold faceplate 73.The inward flow intothe retention feed openings 79 is limited by the ends of the ejectingfingers 85 located in the passages 8t The" :molten plastic injected intothe passage 51 flows through the passage 49, runners 48 and gates 47into the panel mold cavities39 having the previously formed tearportions 13 positioned therein. To achieve the desired seal at theinterface 14 of the preformed outer edge of the tear portion 13 andpanel 12, the temperature and injection pressure of the molten plasticentering the panel mold cavities 39 are controlled to maintain the hatat the interface 14 at a level below that causing the prior formed edgeof the tear portion 13 to lose its configuration. The heat is maintainedat level sufficiently below that causing the formation of an unbreakableseal at the interface 14. lt has been found that the heat should be suchthat upon subsequent solidification of thepanel 12 about the tearportion 13 the latter is securely seated in sealing relationship thereonand capable of being separated along the interface 14 upon the,application of a manually applied force. For opening a container of thegeneral type of which the closure of the present invention is applied,the manual force should preferably be less than about l5 pounds so thatthe force may be applied by the users fingers. A more detaileddescription of 6 During the remainder of the linear movement, theactuating pin 89 enters the aligned opening '87 and 88 and engages theejecting pin slide plate 83, so thatthe ejecting fingers 85 areoperative to eject the completed closure units 10 from the transferplate 73. The forward movement of the slide 'plate'83 also moves thesprue removal pin 94,'into engagement with the sprue and runnersattached to theytear panels 12I'so as to be separated therefrom.

Thereafter the index head 53re tu rns to the closed position to repeatthe operation described above.

Closures 10 have been made in accordance with the foregoing describedmethod in which the tear portion 13 and panel 7 12 were both made fromthe same material. The tear portion 13 was preformed to provide theinterface structure 14 illustrated in FIGS. 2 and 3'..The panel 12 wasmolded thereabout as described heretofore with injection of the plasticto form the panel 12 about the tear portion 13 being carried out underconditions in which the injection pressure was maintained at about 800lbs. per square inch and withaconstant molding time (i.e., time duringwhich the index head assembly 33 and stationary head assembly 32 remainclosed) of about 4.0 seconds. A plurality of runs were performed usingdifferent melt temperatures as determined at the nozzle of the injectionhead and different mold temperatures to vary the seal formed at theinterface 14. v j

A pull tab 16 was attached to the posts 15 of each of the tear portion13 to complete the closure 10. Thereafter the closures 10 from each ofthe runs were tested against specified standards to determine thepopforce required to initiate separation of the seal at the butt joint14a, the pull force required to separate the scarf joint 14b to the wideend; and detachment the pressure and temperature conditions will bedescribed force requiredto complete the separation'of the tear portion13 from the panel 12 at the wide end thereof. The standard pop force isset not to exceed 8 poundsandthe'staridard pull and detachment forcesare set not to exceed 15" pounds respectively. The test was performed onan ln s'tron tensile stress unit which applied a constant strain rate of2 inches per minute on the pull tab 16. i

Table I below tabulates the results obtained when the panel 12 and tearportion 13 are both made from a polypropylene homopolymer having a meltflow of 4.0 and a density of 0.905 and'Table II when the panel 12 andtear portion 13 are both made from a polypropylene copolymer having amelt flow of 3.5 and a density of L898.

Butt joint 14a omilled uhd scarf joint 14h completely extending uhoulinterface l4.

TABLE II 1.8 lbs. 6.8 lbs.

1.5 lbs. 7.9 lbs.

Closures were also formed in accordance with the foregoing methodin'which the panel 12 was made from a plastic of a class different fromthe plastic of the tear portion 13. The molten plastic for forming theclosure 10 was injected at a conare tabulated below in Table III.

Nozzle Temp. Pop Value Pull Value Detach TABLE III 380 F. 80 F. 0.7 lbs.2.0 lbs. 2.0 lbs.

420 F. 80 F. 0.9 lbs. 1.8 lbs. l'.8 lbs.

Referring now to FIG. 13, there is shown a further embodiment of closure200 made in accordance with the present invention. As shown, the closure200 is shown associated with a pour opening 201 of a bottle 202,although it is to be understood that the closure may also be formedabout a wide mouth opening container such as a jar or the like. The pouropening 201 is formed with a retention bead 203 and may be provided withprojections 204 defining a helical screw thread which merges with thebead 203. The screw thread 204 facilitates the removal of the closure200 therefrom.

The closure 200 is in the form of a cap or crown 206 having a top panel207 and an integral depending flange 208. The inner face 209 is joinedto the outer face 210 of the bottle 202 adjacent the mouth at aninterface 211 which defines a weakening line along which the cap 206 isseparable.

The interface or weakening line 211 is formed by preforming either theinner face 209 of the cap flange or skirt 208 or the outer face 210about the pour opening 201 so as to provide a finished mold face onwhich the face of the other member is subsequently molded. The cap 206and bottle 202 may be made from suitable moldable material as forexample, a thermoplastic such as polyethylene, polypropylene and thelike, a thermosetting plastic such as a filled phenolic molding powderor rubber. The compositions of the plastics used to made the cap andbottle may be similar to those heretofore described in connection withthe embodiments of FIGS. 1-6.

The cap 206 and bottle 202 are formed by molding in sequence so that theface is preformed and may be used to form the complementary face of theother. Assuming that the cap 206 is formed first so that the innersurface thereof is preformed, the cap is then positioned into a mold inwhich the bottle is formed. The cap 206 is located in the bottle formingmold (not shown) so as to provide a mold surface for forming theexterior face 210 about the pour opening of the bottle.

The heat of the molding of the bottle is maintained, as describedheretofore, so that upon subsequent solidification of the pour openingportion of the bottle 202 to the cap, the latter is sealed thereto andat the same time capable of being separated along the interface upon theapplication of manual twisting force. The heat to achieve the separableinterface is obtained by controlling the temperature and injectionpressure so that the inner face 209 of the cap 206 forming the mold forthe pour opening portion of the bottle 202 does not loose itsconfiguration. When the heat is controlled in this manner. the interfaceis separable and upon manual twisting each of the faces at the interfacemaintain their integrity.

Various different forms of crown caps or bottle caps may also beconstructed in a manner which permits the partial or entire removal ofthe cap from an associated bottle. In this regard reference is now madeto FIGS. 14 through 19 of the drawings which illustrate a cap generallydesignated by the reference numeral 300 which is secured to a neck N ofthe conventional bottle B.

The cap 300 is of a two-piece construction defined by a removal tear-outpanel portion 302 and a remaining peripheral skirt portion 303. Thetear-out panel 302 and the remaining portion 303 are joined to eachother along a weakening line 304 (FIG. 16) which functions to facilitatethe rupture and subsequent removal of the tear-out panel 302 in a mannerwhich will be more apparent hereafter.

The tear-out panel portion 302 is generally circular and may be slightlylarger than the exterior diameter of the peripheral skirt 303, as isbest illustrated in FIG. 16. A pull tab 305 depends downwardly from thetear out panel portion 302 extends along the peripheral skirt 303 andterminates in a ringlike gripping portion 306 having a finger-receivingopening 307.

The cap 300 is formed by either of two analogous methods whichcorrespond to those heretofore described in connection with theembodiment of FIGS. l-6, wherein the peripheral skirt 303 or thetear-out panel 302 and its integral pull tab 305 is formed first andthereafter the other is molded thereabout.

Assuming that the tear-out portion 302 and its tear-tab 305 areinitially formed from plastic material by a conventional molding processand that the pull tab is in the plane of the tear-out portion, thetear-out portion may be positioned in a split-mold which when closed hasan annular cavity disposed with its axis concentric with the centralaxis of the tear-out portion 302. Molten synthetic polymeric material,such as polyethylene, polypropylene, etc., is then injected into theclosed mold into the annular cavity, and the mold is maintained undercontrolled temperature and pressure as heretofore described which causesthe material in the cavity to mold about the prior molded surface of thetear-out panel portion 302 at the circular interface or weakening line304. Upon cooling the plastic material solidifies along a line or planeof weakness which is separable upon the application of a pulling force.Thus, when the cap 300 is secured to the bottle neck N as for example,by crimping, the lower end of the peripheral skirt 303 as shown andfolding the tear-tab 305 downwardly, the latter is merely lifted andpulled as diagrammatically illustratcd in FIG. 15 causing the tear-outpanel 302 to rupture along the weakening line 304 effecting the eventualcomplete removal of the panel 302 from the peripheral skirt 303. Thecontents packaged in the bottle B can now be dispensed, it being notedthat the peripheral skirt 303 remains on the neck N of the bottle B inaccordance with this embodiment of the invention.

Another method of forming the cap 300 is the reverse of that heretoforedescribed, namely, first forming the peripheral skirt 303 andpositioning the same in a mold having a cavity corresponding to thetear-out panel 302 and its associated pull tab 305. Upon theintroduction of synthetic polymeric material into this cavity the cap300 is similarly formed with the weakening line 304 at the interface ofthe tearout panel 302 and the peripheral skirt 303.

Under some circumstances, it may be desirable to separate the peripheralskirt 303 upon the bottle neck N upon the removal of the tear-out panel302. A closure in the form of a bottle cap for permitting the entireremoval thereof from an associated bottle is shown in FIGS. 17 through19 of the drawings, and is generally designated by the reference numeral310.

The cap 310 is similarly of a two-piece construction defined by aremovable tear-out panel portion 312 in the form ofa pull strip and aremaining portion 313. The tear-out panel 312 and the remaining portion313 are joined to each other along a pair of parallel weakening lines,which are generally designated by the reference numeral 314, 315 and abridging weakening line 316. The weakening lines 314, 315 extend fromthe weakening line 316 across an end panel 317 of the cap 310 and down adiametrically opposite side of a peripheral skirt 318, as is bestillustrated in FIG. 18. A pull tab portion 320 of the tear-out panel 312projects beyond the peripheral skirt 318 and terminates in a grippingring 321 having a fingerreceiving opening 322.

The cap 310 is formed analogous to that heretofore described relative tothe method of forming the cap 300, except for the particularconfiguration of the mold in which the cap 310 is formed. Therefore, itis believed unnecessary for a complete understanding of this inventionto describe the particular method of forming the cap 310. However, itwill be pointed out that by either of the two methods, the weakeninglines 314, 315 and 316 are separable upon the application of an upwardlydirected force to the tear-out panel 312 by gripping and pulling thesame as shown in FIG. 19 results in the complete removal of the panel312. The remaining portion 313 of the cap 310 can now be readily graspedand easily removed as the material of the peripheral skirt 318 can bemanually spread to remove the remaining portion 313 completely from theassociated bottle.

While preferred forms and arrangement of parts have been shown inillustrating the invention, it is to be clearly understood that variouschanges in details and arrangement of parts may be made withoutdeparting from the spirit and scope of the invention as defined in theappended claimed subject matter.

What is claimed is:

1. An article of manufacture comprising a first member and a secondmember connected to said first member at an interface defining aweakening line along which said second member is separable from saidfirst member upon the application of a manual force thereto, saidweakening line being formed by the sequential molding of said first andsecond members using a prior molded face at the interface of one of saidmembers to form the complementary face of the other of said members.

2. The invention as defined in claim 1 wherein said first membercomprises a panel and said second member comprises a tear portion.

3. The invention as defined in claim 2 wherein said panel is formed withan opening defined bya face of said interface and said tear portion isdisposed in said opening with the outer edge thereof defining thecomplementary face of said inter face.

4. The invention as defined in claim 3 wherein said faces at saidinterface are shaped to provide an interlock.

5. The invention as defined in claim 4 .wherein said interlock is formedto permit reinsertion of said tear portion into said opening afterseparation from said panel.

6. The invention as defined in claim 3 wherein said faces at saidinterface are in the form of a scarf joint.

7. The invention as defined in claim 3 wherein said faces at saidinterface are in the form of a butt joint.

8. The invention as defined in claim 3 wherein said faces at saidinterface are in the form of a tongue and groove joint.

9. The invention as defined in claim 3 wherein said faces at saidinterface are in the form of a dovetail joint.

10. The invention as defined in claim 2 wherein said panel and tearportion are both made from a plastic material.

1 1. The invention as defined in claim 10 wherein said plastic materialfrom which said panel is made is the same chemical class as the tearportion but of different physical characteristics.

12. The invention as defined in claim 11 wherein said plastic materialfrom which said panel is made from a plastic of a different chemicalclass than the tear portion.

13. The inventionas defined in claim 10 wherein said panel portion andsaid tear portion are cohesively connected at said interface.

14. The invention as defined in claim 1 wherein said first membercomprises a generally tubular body having an open end, and said secondmember comprises a closure superposed over the open end of said tubularbody.

15. The invention as defined in claim 13 wherein said closure includes adownwardly depending skirt embracing said tubular body to form saidinterface defining said weakening line.

16. The invention as defined in claim 15 wherein said tubular body andsaid closure are both made from a plastic material.

17. In an easy opening container having an opening, a closure memberattachable to said container for covering said opening, said closuremember comprising a panel member having an opening, a tear portionmolded in said panel opening with the edge of the tear portion and theedge defining said panel opening lying on an interface forming a sealand defining a weakening line along which the tear portion is separatedfrom said panel, and finger grip means on said tear portion for applyinga force for separating said tear portion from said panel.

18. The invention as defined in claim 13 wherein said edges at saidinterface are formed to interlock and provide for reinsertion of saidtear portion into said opening.

19. The invention as defined in claim 13 wherein said panel and saidtear portion are both made from plastic.

20. An closure for an open ended container, said closure comprising apanel adapted to overlie the end of said containcr, and a dependingskirt adapted to embrace the exterior of said container about saidopening, said closure including a tear portion formed in said panel andseparable therefrom to provide an opening, saidtear portion being joinedto said panel along an interface defining a weakening line, saidweakening line being formed by a sequential molding of said panel andsaid tear portion using a prior molded face at the interface of one ofsaid tear portion or said panel to form the complementary face of theother.

21. The invention as defined in claim 20 wherein said weakening lineextends into said skirt.

22. The invention as defined in claim 21 wherein said tear portioncomprises a pair of spaced weakening extending from said panel andterminating at the free end of said skirt.

1. An article of manufacture comprising a first member and a secondmember connected to said first member at an interface defining aweakening line along which said second member is separable from saidfirst member upon the application of a manual force thereto, saidweakening line being formed by the sequential molding of said first andsecond members using a prior molded face at the interface of one of saidmembers to form the complementary face of the other of said members. 2.The invention as defined in claim 1 wherein said first member comprisesa panel and said second member comprises a tear portion.
 3. Theinvention as defined in claim 2 wherein said panel is formed with anopening defined by a face of said interface and said tear portion isdisposed in said opening with the outer edge thereof defining thecompleMentary face of said interface.
 4. The invention as defined inclaim 3 wherein said faces at said interface are shaped to provide aninterlock.
 5. The invention as defined in claim 4 wherein said interlockis formed to permit reinsertion of said tear portion into said openingafter separation from said panel.
 6. The invention as defined in claim 3wherein said faces at said interface are in the form of a scarf joint.7. The invention as defined in claim 3 wherein said faces at saidinterface are in the form of a butt joint.
 8. The invention as definedin claim 3 wherein said faces at said interface are in the form of atongue and groove joint.
 9. The invention as defined in claim 3 whereinsaid faces at said interface are in the form of a dovetail joint. 10.The invention as defined in claim 2 wherein said panel and tear portionare both made from a plastic material.
 11. The invention as defined inclaim 10 wherein said plastic material from which said panel is made isthe same chemical class as the tear portion but of different physicalcharacteristics.
 12. The invention as defined in claim 11 wherein saidplastic material from which said panel is made from a plastic of adifferent chemical class than the tear portion.
 13. The invention asdefined in claim 10 wherein said panel portion and said tear portion arecohesively connected at said interface.
 14. The invention as defined inclaim 1 wherein said first member comprises a generally tubular bodyhaving an open end, and said second member comprises a closuresuperposed over the open end of said tubular body.
 15. The invention asdefined in claim 13 wherein said closure includes a downwardly dependingskirt embracing said tubular body to form said interface defining saidweakening line.
 16. The invention as defined in claim 15 wherein saidtubular body and said closure are both made from a plastic material. 17.In an easy opening container having an opening, a closure memberattachable to said container for covering said opening, said closuremember comprising a panel member having an opening, a tear portionmolded in said panel opening with the edge of the tear portion and theedge defining said panel opening lying on an interface forming a sealand defining a weakening line along which the tear portion is separatedfrom said panel, and finger grip means on said tear portion for applyinga force for separating said tear portion from said panel.
 18. Theinvention as defined in claim 13 wherein said edges at said interfaceare formed to interlock and provide for reinsertion of said tear portioninto said opening.
 19. The invention as defined in claim 13 wherein saidpanel and said tear portion are both made from plastic.
 20. An closurefor an open ended container, said closure comprising a panel adapted tooverlie the end of said container, and a depending skirt adapted toembrace the exterior of said container about said opening, said closureincluding a tear portion formed in said panel and separable therefrom toprovide an opening, said tear portion being joined to said panel alongan interface defining a weakening line, said weakening line being formedby a sequential molding of said panel and said tear portion using aprior molded face at the interface of one of said tear portion or saidpanel to form the complementary face of the other.
 21. The invention asdefined in claim 20 wherein said weakening line extends into said skirt.22. The invention as defined in claim 21 wherein said tear portioncomprises a pair of spaced weakening extending from said panel andterminating at the free end of said skirt.